drm_hwcomposer: add overlapping rectangle seperation algorithm
Change-Id: I40734ce77191ac37fb2a2c156d6010530df0434b
diff --git a/seperate_rects.h b/seperate_rects.h
new file mode 100644
index 0000000..9bf95a3
--- /dev/null
+++ b/seperate_rects.h
@@ -0,0 +1,140 @@
+/*
+ * Copyright (C) 2015 The Android Open Source Project
+ *
+ * Licensed under the Apache License, Version 2.0 (the "License");
+ * you may not use this file except in compliance with the License.
+ * You may obtain a copy of the License at
+ *
+ * http://www.apache.org/licenses/LICENSE-2.0
+ *
+ * Unless required by applicable law or agreed to in writing, software
+ * distributed under the License is distributed on an "AS IS" BASIS,
+ * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+ * See the License for the specific language governing permissions and
+ * limitations under the License.
+ */
+
+#ifndef DRM_HWCOMPOSER_SEPERATE_RECTS_H_
+#define DRM_HWCOMPOSER_SEPERATE_RECTS_H_
+
+#include <stdint.h>
+#include <vector>
+
+namespace seperate_rects {
+
+template <typename TFloat>
+struct Rect {
+ union {
+ struct {
+ TFloat left, top, right, bottom;
+ };
+ struct {
+ TFloat x1, y1, x2, y2;
+ };
+ TFloat bounds[4];
+ };
+
+ typedef TFloat TNum;
+
+ Rect() {
+ }
+
+ Rect(TFloat xx1, TFloat yy1, TFloat xx2, TFloat yy2)
+ : x1(xx1), y1(yy1), x2(xx2), y2(yy2) {
+ }
+
+ Rect(const Rect &rhs) {
+ for (int i = 0; i < 4; i++)
+ bounds[i] = rhs.bounds[i];
+ }
+
+ bool operator==(const Rect &rhs) const {
+ for (int i = 0; i < 4; i++) {
+ if (bounds[i] != rhs.bounds[i])
+ return false;
+ }
+
+ return true;
+ }
+};
+
+template <typename TUInt>
+struct IdSet {
+ public:
+ typedef TUInt TId;
+
+ IdSet() : bitset(0) {
+ }
+
+ IdSet(TId id) : bitset(0) {
+ add(id);
+ }
+
+ void add(TId id) {
+ bitset |= ((TUInt)1) << id;
+ }
+
+ void subtract(TId id) {
+ bitset &= ~(((TUInt)1) << id);
+ }
+
+ bool isEmpty() const {
+ return bitset == 0;
+ }
+
+ TUInt getBits() const {
+ return bitset;
+ }
+
+ bool operator==(const IdSet<TId> &rhs) const {
+ return bitset == rhs.bitset;
+ }
+
+ bool operator<(const IdSet<TId> &rhs) const {
+ return bitset < rhs.bitset;
+ }
+
+ IdSet<TId> operator|(const IdSet<TId> &rhs) const {
+ IdSet ret;
+ ret.bitset = bitset | rhs.bitset;
+ return ret;
+ }
+
+ IdSet<TId> operator|(TId id) const {
+ IdSet<TId> ret;
+ ret.bitset = bitset;
+ ret.add(id);
+ return ret;
+ }
+
+ static const int max_elements = sizeof(TId) * 8;
+
+ private:
+ TUInt bitset;
+};
+
+template <typename TId, typename TNum>
+struct RectSet {
+ IdSet<TId> id_set;
+ Rect<TNum> rect;
+
+ RectSet(const IdSet<TId> &i, const Rect<TNum> &r) : id_set(i), rect(r) {
+ }
+
+ bool operator==(const RectSet<TId, TNum> &rhs) const {
+ return id_set == rhs.id_set && rect == rhs.rect;
+ }
+};
+
+// Seperates up to a maximum of 64 input rectangles into mutually non-
+// overlapping rectangles that cover the exact same area and outputs those non-
+// overlapping rectangles. Each output rectangle also includes the set of input
+// rectangle indices that overlap the output rectangle encoded in a bitset. For
+// example, an output rectangle that overlaps input rectangles in[0], in[1], and
+// in[4], the bitset would be (ommitting leading zeroes) 10011.
+void seperate_frects_64(const std::vector<Rect<float> > &in,
+ std::vector<RectSet<uint64_t, float> > *out);
+
+} // namespace seperate_rects
+
+#endif